by Dinesh Thakur Category: Servlet with MySql Database

This Function will Converts a day number to a Date.

Then i use to make a database named 'dbase' that is been built in the reference of mySql(php ,yAdmin). Then i import all the required java packages from java library. Then i made a class named ‘MySqlFromDays’, which extends 'HttpServlet'. Then i use service()Method that will use to getting the request from doGet()Method for output on the web browser. Then i loaded all the required drivers for the database accessing. Then i declare mandatory variables i use 'connection' this variable will use to create a link between database and the java code. Then i use 'resultSet' that return the value from selected columns and rows from table as required. Other i declare 'preparedStatement' that will use to executing the selected query like executeQuery() as (Select FROM_DAYS((365*2014)). I use doGet()Method for output on the web browser.

To get output on the web browser i use 'HTML' code and tags which present it in tabular form.

import java.io.IOException;

import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class MySqlFromDays extends HttpServlet
 {
      public void service(HttpServletRequest rq, HttpServletResponse rp)throws IOException, ServletException
        {
            rp.setContentType("text/html");
            PrintWriter disp = rp.getWriter();
            String driver = "com.mysql.jdbc.Driver";
            String url = "jdbc:mysql://localhost/dbase";
            String uid = "root";
            String psw = "root";
            Connection con=null;
            PreparedStatement ps = null;
            ResultSet rs;
            try
             {
                  Class.forName(driver);
                  con = DriverManager.getConnection(url,uid,psw);
                  ps=con.prepareStatement("Select FROM_DAYS((365*2014)) AS st");
                  rs = ps.executeQuery();
               String title = "Using From_Days Function";
                 String docType ="<!doctype html public \"-//w3c//dtd html 4.0 " + "transitional//en\">\n";
               disp.println(docType + "<html>\n" + "<head><title>" + title + "</title></head>\n" +
                 "<body bgcolor=\"#f4efef\">\n" + "<h1 align=\"center\">" + title + "</h1>\n" + "<ul>\n" +
               "<table width=\"50%\" border=\"1\" align=\"center\">\n" + "<th>Start Of 2014</th>\n"+ "</body> </html>");
                 while(rs.next())
                     {
                           String curr = rs.getString(1);
                        disp.println("<tr><td align=\"center\">" + curr +"</td></tr>" );  
                     }     
              }       
                        catch(Exception e) 
                              {
                                   e.printStackTrace();
                              }
                                   disp.close();
       }
                                     public void doPost(HttpServletRequest rq,HttpServletResponse rp)throws IOException,ServletException
                                      {
                                         doGet(rq,rp);
                                      }
 }
WEB.xml
 
<servlet>
   <servlet-name>MySqlFromDays</servlet-name>
   <servlet-class>MySqlFromDays</servlet-class>
</servlet>
<!-- servlet mapping -->
<servlet-mapping>
   <servlet-name>MySqlFromDays</servlet-name>
   <url-pattern>/MySqlFromDays</url-pattern>
</servlet-mapping>




About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.



Related Articles